TW440635B - Textured impermeable papermaking belt, process of making, and process of making paper therewith - Google Patents

Abstract

An impermeable papermaking belt. The papermaking belt has a back side and a sheet side. The sheet side of the papermaking belt is textured. The sheet side imparts structure, preferably differential density, to paper made on the impermeable belt. The papermaking belt may comprise photosensitive resin on the sheet side. The papermaking belt may be used in conjunction with an imprinting roll which densifies the regions of the paper coincident the knuckles of the papermaking belt. This belt is suitable for papermaking machines having or not having a Yankee drying drum.

Description

V. Description of the invention ¢ 1) Background of the invention The present invention relates to papermaking belts, particularly impermeable belts that reduce the risk of paper re-wetting, and more particularly impermeable belts that can produce structured tissue paper. Manufactured paper, and methods of making such paper and belts. BACKGROUND OF THE INVENTION Papermaking belts are well known in the art. Papermaking belts are used in paper machines to dehydrate and transport cellulose fibers. Cellulose fibers turn into germ paper and become finished after drying. Generally speaking, papermaking belts do not give the structure of the paper made on them. " Structure π refers to the variation in unit weight and / or more specifically, the density of paper, which is greater than that of ordinary papermaking, and is caused by ordinary variations, such as 纟 or wet micro shrinkage (we ΐ micr 〇- c ο η rac rac ΐ i ◦ η). These papermaking belts can be vented drying belts or conventional press felts. These belts contain a skeleton and a reinforcing structure, from which water is removed ° Structured paper is a favorite for consumers because paper is softer, more absorbent, and uses less fiber. However, manufacturing structured paper generally requires aeration and drying, which can be costly. A disadvantage of the above-mentioned types of papermaking belts which are known to make structured paper is that these papermaking belts are water-permeable and water-permeable, and there is a risk that the belts will absorb moisture again. Re-hygroscopic occurs when water removed from the paper made on the belt is removed from the paper and then returned to the paper. There are many reasons for re-hygroscopicity. Typical causes of re-absorption include excess water from the belt where the paper enters. Impervious belts are also known in the art. For example, one type is already on the market

V. Description of the invention (2) —----- Impermeable belts sold by u, named Trans —belt, A1 ^ ny international company any ,, .γ) DTrans-beU (conveyor belt) and previous Skill ^ Second, his inferior leather belts all have disadvantages, that is, they will not make structured paper as they wish. One attempt to avoid this disadvantage in this technique is to provide a patterned imprin1 (ing r0n). The embossed embossing roller is juxtaposed with the impermeable belt to form a jaw therebetween. The paper advances through the jaws between the belt and the embossing roller. In the molybdenum port, the pattern is printed on the paper to produce a structured paper. The structured paper is then advanced to the pressure roller, where it is pressed by the first sweet mouth between the pressure roller and the Yankee supply tank. However, at a light pressure, the structure previously printed on the paper is reduced or even disappeared due to the compaction of this second jaw. The compaction of the second sweet mouth between the pressurized newspaper and the Yankee oven will flatten the paper 'and cause structural loss caused by the jaws between the conveyor belt and the printing roller. The invention provides a paper machine having an impermeable belt. Furthermore, the present invention provides a belt for such a paper machine, which belt can produce structured paper. The present invention makes it possible to manufacture structured paper on an impermeable belt without reducing the structure in the steps attached to the manufacturing process. SUMMARY OF THE INVENTION The present invention includes an impermeable papermaking belt. Impervious papermaking belt has front and back sides, one paper side and one back side. The paper surface will give paper structure when making paper. The paper surface of the papermaking belt is structured. Brief Description of the Drawings Figure 1 is a representative papermaking process with impervious belts in the press section of the prior art

Page 6 4〇6 3¾ 5. Description of the invention (3) ------------ vertical side view of the machine. Fig. 2 is a vertical side view of a part of the papermaking belt of the present invention. Fig. 3 is a double-mesh papermaking machine of the present invention. Fig. 4 is an enlarged vertical view of a part of the papermaking machine of Fig. 3. Straight side view, which is not so bad but can be operated with f (dotted line) and better cloth operation (solid line). Fig. 5 is a vertical side view of the fixed roof paper machine ' Detailed description of each invention of the angle knife valve 凊 Refer to FIG. 1, which shows a representative paper machine of the prior art. Paper machine 10 has first-class bins 1 2. The headbox 12 distributes the fibrous fibrous bodies dispersed in the liquid carrier on the forming wire 14. The carrier is drained through a forming wire 14 'to produce a blank sheet of paper 22. The '' 'Zhang 2 2 is moved from the forming wire 4 to the impermeable dry backing wire. The impervious network system is arranged in the press section of the paper machine. The paper 22 is moved from the drying lining to any drying device known in the art. Representative drying devices include infrared dryers, ventilating dryers, and Yankee drying ovens as appropriate. The paper 22 can be renewed using a cracking method known in the art. If necessary ', the paper 22 can be pressed between two rollers, i.e., a pressure roller 24 and a support roller 26, when it is on the drying liner. The pressure roller 24 and the support roller 26 are juxtaposed to form a jaw therebetween. The paper 22 passes through this jaw to squeeze out some of the water contained in the paper 2 2. If necessary, an optional felt can be placed between the paper 2 2 and the pressure roller 2 4. The paper 22 can also be crimped, as known in the art. Creping can be accomplished by creping the paper from a hard surface, preferably from a cylinder. Yankee Oven

Page 7 _ 5. Description of the invention (4) For this purpose. Creping can be accomplished in accordance with US Patent No. 4,919,756 (issued to Sawdai on April 24, 1992), which is generally assigned, the disclosure of which is hereby incorporated by reference. Alternatively, or in addition, creping can be accomplished by wet microcontraction, as taught by U.S. Patent No. 4,440,597, which was generally assigned (April 1984: issued to We 1 1s et al. On April 3), which The contents are disclosed and incorporated herein by reference. The paper 2 2 manufactured on the paper machine 10 of FIG. 1 is not structured because no device exists to give the paper 22 a difference in unit weight, or a better difference in density. As used herein, "structured" paper 2 2 has regions of mutually different unit weights or densities arranged in a non-random repeat pattern throughout the paper. An attempt to improve the paper machine 10 of Fig. 1 was to use an impervious drying liner Screen and embossing embossing roller. The embossing embossing roller will be in the jaw between the embossing embossing roller and the support roller. Paper 2 2 embossing, as discussed above. Paper 2 2 embossing, the structure is on the paper 22 is formed. However, the structure is only maintained until the paper 2 2 passes through the jaw formed between the dry transfer roller and the Yankee oven 2 G. In the jaw, most, if not all, of the structure will be compressed from the paper 2 2 Lost, basically returned to its original flat state. | Please refer to Figure 2, the belt 15 of the present invention is impermeable and will give the pattern of paper 22 made on it. The belt of the present invention has a paper The surface 30 and the back surface 32. The paper color surface 30 is structured, and is a surface that contacts, transports, and gives structure to the paper 22 in ordinary use. The back surface 32 of the belt is in papermaking with the paper machine 10, And especially the driving device of the paper machine 10 is in contact with the driving roller. Generally speaking, the paper surface 30 of the belt is facing outward, and the back surface 32 of the belt is facing inward. 4 A 〇β 3 5 V. Description of the invention (5) The papermaking belt 15 of the present invention is a macroscopic single plane. The paper machine 15 determines its X-Υ direction. It is perpendicular to the X-Υ direction of the paper-making belt and the Z-direction of the plane. Similarly, the paper 2 2 'of the present invention can be regarded as a macro and located on the X-Υ plane. It is perpendicular to the X-Υ direction of the paper 22 and the Z-direction of the paper 1. The belt 15 is examined in more detail. It can be found that the belt 15 of the present invention includes the main components: a skeleton 42 and a reinforcing structure 44. The skeleton 42 is arranged at j The paper surface defines the structure. The framework 42 preferably includes a hardened polymeric light framework 42. The structure defines a predetermined pattern, which is the same as the paper 22 of the present invention. The special pattern of the framework 42 is basically a structure. 4 2 If a better substantially continuous mesh pattern is selected, 46 will extend between the first surface and the second surface of the belt 15. The base mesh surrounds and defines the blind hole. The second surface of the belt 15 is where the belt 15 contacts the machine The surface can be made with a back net structure, which is provided separately from the blind hole 4 6 The irregularity of the structure of the second surface of the second surface of the belt 15. The channel leaks in the X-Υ plane of the belt 15, and the leakage does not necessarily pass through the blind hole 46 of the belt 15 in the Z-square. The second main component of the belt 15 of the present invention It is a reinforcing structure 44. 44, like the skeleton 42, has the first or paper-facing side and the paper-facing side opposite to the machine-facing side. The reinforcing structure 44 is mainly between the opposite sides of the belt, and may have the back side of the belt 15 The strong structure 44 provides support for the skeleton 42. If we don't want to weave the woven fabric in the reinforcement, the non-woven element, screen, mesh or the plane boundary among them is the single plane of the belt. One main resin with 15 sensitive resins. The case is embossed on the continuous web, discrete blind holes, and continuous second surface channels. The channel allows air to flow and strengthen the knot. The structure or the surface is arranged on the skin surface. The use of the supplementary structure 44 has a large number of holes. 5. The plates of the invention description (6) can provide sufficient strength and support for the framework 4 2 of the present invention. The belt 15 of the present invention can be assigned according to any of the following US patent systems that are generally assigned: 4,514, 345 (issued to Johnson et al. On April 30, 1985), No. 4,528,239 (issued on July 9, 1985 To Trokhan); 5, 0 98, 5 2 2 (March 24, 1992); 5, 2 6 0, 1 71 (Awarded to Smurkoski et al. On November 9, 1 99); 5 No. 5, 275, 70 (issued to Trokhan on January 4, 994); 5, 328, 565 (issued to RaSch et al. On July 12, 1994); '5,334, 289 (August 2, 1994 Dated to Trokhan et al.); No. 5, 431, 786 (to Rasch et al., July 11, 1995); No. 5, 4 96, 624 (to Stelljes Jr., March 5, 1996 Et al.); 5,500, No. 7 (issued to Trokhan et al. On March 19, 1996); No. 5,514,523 (issued to Trokhan et al. On May 7, 1996); No. 5,554,467 (September 10, 1996 Awarded to Trokhan et al.); 5, 5, 66, 724 (issued October 22, 1996

Trokhan et al.); 5,624,790 (issued to Trokhan et al., April 29, 1997); and 5,628,876 (issued to Ayers, et al., May 13, 1997), disclosure of these patents The contents are incorporated herein for reference. The moon frame 4 2 can be applied to Shuo Bu by the teachings of the United States patents that are summarized and transferred | Strong Structure 44: 5, 556, 509 (issued to Trokhan et al. | September 17, 1996 | People), 5,580,423 No. (issued to Ampulski et al. On December 3, 1996); No. 5,609,725 (to phan on March 11, 1997); No. 5,629, 052 (to May 13, 1997 Trokhan et al.); 5, 6 37, 1 94 (issued to Ampulski et al. On June 10, 1997) and 5, 674, 6 6 3 (issued to October 7, 1997 Me Far land et al.), The contents of these patents are incorporated herein by reference.

Page 10 at 40′B; 3..b 5. Description of the invention (7) According to the present invention, a suitable belt 15 can be manufactured using the above-mentioned photosensitive resin. Representative methods of making such belts 15 have been described in several patents above and hereby incorporated by reference. However, the differences required to complete the manufacturing process from previous techniques are stated below. First, a liquid photosensitive resin is provided. The resin is arranged on a support surface, usually a large roll. A mask having transparent and opaque areas and a photosensitive resin are juxtaposed and preferably placed thereon. Actinic radiation is passed through the transparent areas of the mask. Radiation that passes through the transparent area of the mask will harden the trees underneath it, creating impervious belts 15. However, it is important that the belt 15 is not only impermeable but also structured on the paper surface 30. By "structure" is meant that the belt 15 has an outer configuration that can press the structure into the paper 22, and more specifically, it can give the paper 22 a differential density during normal papermaking. The structure has a Z-direction roughness that exceeds that of normal and ordinary belt manufacturing methods used for impermeable belts. The roughness in the Z-direction preferably has a depth of at least about 0.02 inches, more preferably at least about 0.05 inches, still more preferably at least about D. 0 10 inches, and still more preferably at least about 0. 15 inches, but preferably not more than 0.50 inches. The preferred range for making absorbent, thick, soft and pleasing cotton paper is about 0.010 to 0.030 inches. The structure is given to the belt 15 as follows. The radiation is fired in a direction perpendicular to the plane of the belt 15 and off-axis, that is, in a non-vertical direction. Providing off-axis radiation, the resin aligned with the opaque areas of the mask and underneath, and the resin aligned with the transparent areas of the mask will harden. However, the hardening under such opaque areas occurs to a certain depth below the mask. The resin area immediately below the opaque area of the mask will not harden because of the incident angle of radiation. Off-axis,

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5. Description of the invention (8) That is, non-vertical radiation must be sufficient to harden the resin on the entire surface of the 15 X -Y plane of the belt. Taking the specific example described here, a mask with an elliptical opaque region whose principal axis is in the X-Y plane is 0.8 and 0.06 inches, and the actinic radiation deviates from the vertical angle of about + or -10 degrees, It was found to be suitable for making thick tarts in the form of blind holes 46 with a depth of about 0.015 mm. Radiation may be scattered from the source or self-reinforcing structure 4 4 and scattered off-axis. Of course, a little bit of this artist will recognize that the X-Y dimension of the coarse degree will be matched with the X-Y dimension of the opaque area in the mask. The belt described herein is considered to be impermeable to water. By "impermeable", it is meant that the belt will not transmit water through any capillary having a size of 50 microns or greater. If necessary, the impermeable belt 15 can be made into several other specific examples. For example, impermeable It is not necessary to use the reinforcing structure 4 4 for the belt 15. If necessary, the impermeable belt 15 can be made of the above-mentioned photosensitive resin on the surface without the reinforcing structure 4 4. Polyurethane foam has also been successfully used In order to make the belt impervious, as shown by the commercially available Trans-belt. Or, it is predicted that the rubber and stone ketone coatings can be used to make the belt impermeable. The material that makes the belt impermeable can be used.

What are the known methods, such as printing, spraying, knife coating, other coating techniques or preferably dip application. Impregnation is performed by immersing the belt in a bath of the substance. As appropriate, the belt of the present invention can be made to have a structure that includes a semi-continuous, continuous, or discrete pattern on the X-Y plane of the leather I belt or a combination thereof. If a discrete pattern is required, a papermaking belt with discrete outwardly extending joints can be used. Such a suitable belt of the present invention can be summarized in U.S. Patent No. 4,239,065 (issued 1'1 * 〇] ^ 11 &: 1, the disclosure of which is hereby incorporated by reference) |

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I A 5. Production of the belt disclosed in (9) or Spectra Membrane sold by the Scapa Group (UK). Whether it is the above-mentioned belt or Spectra belt manufactured according to U.S. Patent No. 4 ’239’ 065, which is generally transferred, the depth of the joint is extended into the liquid resin without immersing the belt. It will be hardened as described above to make the belt impervious, leaving a joint diagram, so the impervious belt 1 5 is # retained its original paper surface 30 structure. After the belt 15 becomes permeated by any means or material, the structure can be imparted to each of the photosensitive resins on the leather f5. Alternatively, the structure may be stitched or selectively removed from the material of the belt to provide a ° structure, which may include any desired X-Y pattern regardless of how it is imparted or how the belt is manufactured. The eunuch structure can be discontinuous, semi-continuous, or preferably continuous. A more predictable specific example is the use of impervious conventional felts. The impervious back 3 2 is coated with a material to make the felt impervious. The limbs are then keyed into the paper surface 30 of the oyster to provide an absorbing joint on the top surface of the felt. In this way, it is possible to have the structure that imparts the structure, and at the same time absorb the water from the paper 2 2 joints that are precious &. As used herein, a joint refers to a pattern that protrudes above the paper surface of the belt and extends outward. Referring to Figs. 3-4, the belt of the present invention is used in a paper machine 10 without significantly changing its original configuration. According to the present invention, the paper machine 10 is preferably provided with two misalignments' although the single jaw configuration described above is sufficient. In the preferred two-jaw configuration, there is a support roller 26 juxtaposed with the vacuum pressure roller 24 to form a first sweet mouth, and juxtaposed with the printing roller 28 to form a second jaw. The vacuum pressure roller 24 dehydrates the paper 22 to increase its consistency. The impermeable belt 1 5 embosses the paper 2 2, and the jaw between the pattern 2 8 and the support roller 2 6 gives the paper structure. '

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V. Description of the invention (10) The acquaintance knows the γ technique, and can be treated + understand 'depending on the desired configuration of the paper machine 10, if it will not be brought to the crane, a dual-network configuration will be used. In this case, the paper 22 is referred to in FIG. 5, and the paper impervious belt 15 on the felt 17 is on the paper 2 and on the paper 14. Please bring it back to the jaw, ^ can be transferred from the forming wire 14 to the impermeable belt 丨 5, but ^ ^ a can also be used here. It is important to note that the paper 99 is not transferable to the impermeable belt without the use of vacuum fillet f forming net 14 or felt 17. It is feasible. Therefore, ^ ^ is feasible, because it will be very helpful if the impermeable belt 15 is not expanded. The impermeable belt 15 is shown to the forming wire 14 as shown in the preferred configuration. The forming wire 14 and the The healing belt 15 misses 3 angles, although an angle as large as 90 degrees may be appropriate. The convergence can be turned by the picture shown below < 角 J 此 通 田 _ can be inert with the figure stick; 5 ° auxiliary. Alternatively, set the tension and compression force of the rotating rod belt 15 to change the position where the forming net 14 and the non-permeate JSI U 3 & he points to the direction where the force and centrifugal force point. Forming — — skin ……, — Run an appropriate distance. There is a need for a 'paper machine' on the right. An extension jaw press that can be used as an impression roller 28. An appropriate extension jaw press can be manufactured according to the following: US Patent 5 '650' 049 (1 9 Awarded to Kivivaa and others on July 22, 1997 and surrendered

Valmet); No. 5 '6 62, 7 77 (issued to Schiel et al. And assigned / degrees to Voith on September 2, 1997), or patent application WO95 / 16821 (June 21, 1995 Announced and transferred to Be]: oit) in the name of Mentele, their disclosures are hereby incorporated by reference. In the present invention, the 'paper 22' keeps mating with the structure of the belt until the paper moves to the Yankee oven 20, and the structure imparted to the paper 22 does not disappear after the transfer. Of course, you should know that paper 2 2 can be dried in any number of ways.

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Claims (1)

r_-" A〇6 3. _ 6. Scope of patent application 1. An impervious papermaking belt having a paper surface and an opposite surface, wherein the paper surface will give a paper structure manufactured thereon during papermaking. 2. A papermaking belt. The papermaking belt is impermeable and has a paper surface and an opposite surface. The paper surface of the papermaking belt is structured. 3. The belt according to item 2 of the scope of patent application, wherein the belt contains a photosensitive resin, and the photosensitive resin is arranged on a paper surface of the belt. 4. The belt according to item 3. of the patent application scope, wherein the photosensitive resin contains a substantially continuous network. 5. The papermaking belt according to item 3 of the patent application scope, wherein the belt further includes a reinforcing structure. 6. The papermaking belt according to item 5 of the scope of the patent application, wherein the reinforcing structure includes a view 13 7. A method of manufacturing an impervious papermaking belt, the method includes the following steps: providing a liquid photosensitive resin; providing a mask, the masking tool There are transparent areas and opaque areas; juxtaposing the mask with the resin, so that the first plurality of areas of the resin are juxtaposed with the transparent areas of the mask; passing actinic radiation through the transparent areas of the mask and entering the resin, As a result, the actinic radiation will make the resin partially hardened in the area juxtaposed with the mask. * The actinic radiation is provided at various angles to the plane, at least some of which are not perpendicular to the plane of the mask. To harden the resin portion juxtaposed with the opaque area of the mask; L: \ 56 \ 56317. PTD Page 16-VI. Scope of Patent Application Remove the mask from the resin; and remove the unhardened resin to produce a papermaking belt with a structure that is defined by the hardened resin. 8. The method according to the scope of application for patents Jing ~ §, further comprising the step of providing a reinforcing structure; and disposing the reinforcing structure in the resin. 9. The method according to item 8 of the scope of patent application, wherein the primary supplier of the reinforcing structure is substantially impermeable. 1 0. A method of papermaking, the method comprising the steps of: providing a blank paper sheet; and providing an impervious papermaking belt. The impervious papermaking belt has a paper surface and an opposite backside, and the impervious papermaking belt The paper surface has a structure; the paper is arranged on the paper surface of the impermeable belt; an embossing roller is provided side by side with the paper to form a jaw; the paper is passed through the jaw to make the impermeable papermaking belt The structure imparts the paper structure; and the paper is dried while maintaining its structure. 1 1. The method according to item 10 of the scope of patent application, wherein the step of drying the paper includes the step of moving the paper from the impermeable papermaking belt to a Yankee drying oven. 12. The method according to item 10 of the scope of patent application, further comprising the steps of: providing a felt, and placing the felt in the jaw so that the paper is between the view and the impermeable belt. 1 I 1 I I 1 p. 17